Alarm for fire-extinguishing systems.



Patented Feb. ll, I902.

F. GRAY. ALARM FOR FIRE EXTINGUISHING SYSTEMS.

(Application filed June 11, 1897.)

3 Sheets-Sheet I.

(No Model.)

No. 693,322. Patented Feb; 1902.

F GRAY.

ALARM FOB FIRE EXTlNGUlSHING SYSTEMS. .(Appliggtiop fileq -u z l e 11, 1897.)

(No Model-.9 3 S hee ts$heat a.

j v k k P, I f v M *1 m 1 a G finesiswst c3 uexfiow UNrrEo Tamas ATEN @FFICE.

FRANK GRAY, OF CHICAGO, ILLINOIS.

ALARM FOR FIRE-EXTIN GUISHING SYSTEMS.

' SIEGJEFKO'ATION forming part of Letters Patent No. 693,322, dated February 11 1962.

Application filed .Tiinell, 1897. Serial No. 340,359. (No model.)

which the following is a specification.

In automatic sprinkler systems elect rically operated alarms have been provided, the active operation of which is initiated by closing the circuit, both in dry and wet pipe systems, through the instrumentality of a valve located at a point between the distributing part of the system and the source'of supply. In such an arrangement it is necessary to provide circuit-wiring from the valve to each of the alarms with consequent difficulties resulting from the breaking of the wires, short circuiting, induction, and the like. So, also, it is difficult, if notimpossible, to wire a buildin g with that degree of perfectness necessary to insure invariable action of the alarms in case of a fire or to maintain the wiring in such a perfect condition.

The object of my invention is to provide means for operating the alarms electrically, such as shall render unnecessary the extension of circuit-wiring from the valve to each alarm, and. thus overcome the enumerated and other disadvantages of the present systerns.

My invention has certain other objects in view and.- consists in certain features about to be described, reference being now had to the accompanying drawings, in which- Figure 1 is a front elevation of the alarm. Fig. 2 is a section on the line w a: of Fig. 1. Fig. 3 is a detail view of a portion of the in dicator face, the adjustable contact strip being removed. Fig. 4 is a view showing the interior of building and also showing the alarms as applied to a dry-sprinkler system. Fig. 5 is a like view showing the alarms as applied to a wet-pipe system.

In carrying out my invention I provide a self-contained electrically-operated alarm the action of which is initiated by a circuit-closer in proximity to the alarm apparatus, the alarm apparatus and the circuit-closer being assembled together, so that the alarms, consisting of these elements, are distributed at the various desired locations throughout the build ing, and each is independently operative of one another and of any valveor like instrumentality. I provide apressure-indicator 20, having a conducting-face 21 with suitable readings and'also the index-pointer 22. The indicator is mounted upon a suitable backboard 23, upon which also the batteries 24. and alarm mechanism 25 are mounted. The batteries are connected together by a lead 011 the rear of the board 23 and with the conducting face-plate 21 by the lead 26 through the metal rim 27, on which is the binding-post 28, to which said lead 26 is connected. The pointer 22 is electrically connected with the face-plate 21. Adj ustably mounted upon the rim 27, but insulated therefrom, are the low air-alarm contact-strip 29 for the .dry-pipe system and the reduced water-alarm contactstrip 30 for the wet-pipe system, the bindingpost 31 being connected with the air-alarm strip 29, and the bin ding-post 32 being likewise connected with the strip 30, as shown in Fig. 2. These two binding-posts are connected together by the lead 33. The alarm apparatus 25 is included in circuit with the strip 30 and the batteries by the leads 34: and 35. It is evident, therefore, that the pointer 22 acts as i a circuit-closer and closes the circuit to the alarm apparatus by coming in contact with either the contact-stri p 29 or the contact-strip 30. Thus if the pointer contact withthe strip 29 the circuit through, the alarm apparatus will be completed and the alarm sounded, and if it contact with the strip 30 a like result follows. I

The contact-strip 30 is adjustable about the perimeter of the indicator for the purpose-of sounding the alarm at various different pressures by means of the construction as follows: The face-plate 21 is recessed at 36, Fig. 3, and in this slot is the holding-flange 37, Fig. 2, of the contact-strip 30. A screw secured to said flange 37 (designated at 38) extends into the binding-post 32, this screw being insulated from the rim 27 and adapted to be slid back and forth within a slot within said rim. By

this means the binding-post 32 is attached to the strip 30 and is adapted to be moved back and forth about the rim 27 in order to position the contact-strip at different points upon the perimeter of the indicator, and thus the circuit-closing point may be adjusted relative to a desired given pressure. The pointer 22 is actuated by mechanism of the usual character employed in pressure-indicating gages, and although I have described the face-plate 21 as a conductor for the current from the binding-post 28 to the pointer, it is evident that a special conducting-wire may be employed or the current may pass through the connected train of mechanism to said pointer. The indicator is connected by a pipe 39 to one of the distributing-pipes 40 of the system, whether the same be a wet or a dry pipe system, as shown in Figs. 4: and 5.

An alarm is located in each one of the apartments of the building and connected with one of the distributing-pipes of the system and operates in the manner following: Referring to the wet-pipe system, the gage or indicator would have its pointer 21 in a position beyond the contact-strip 30, and, as shown, the pressure in the system would be over one hundred pounds. Should the sprinkler-heads 41 of the system or any one of them be opened by fire, thus reducing the pressure, the pointer 22, constituting a circuit-closer, would immediately fall back and contact with the strip 30, thus closing the circuit through the batteries and the alarm apparatus. Referring to the dry-pipe system and assuming that the pressure of air is normally maintained at, say, thirty pounds, the pointer indicates such pressure visually, and upon a reduction of such air-pressure the circuit-closer pointer 22 will engage the contact-strip 29, thus closing the circuit through the batteries and the alarm mechanism and sounding the alarm. If the reduction of the air-pressure is occasioned by the opening of a sprinkler-head, the circuit-closer pointer 22 will first contact against the strip 29 and afterward under the influence of the incoming water-pressure the said circuit-closer pointer will advance to and contact with the strip 30 to close the circuits and provide a continuous alarm.

The adjustments of the contact-plates 29 and 30 (shown in Fig. 1) are fora wet-pipe system having a pressure in the distributingpipes of over one hundred pounds and a pressure in the main beyond the main check-valve of between sixty and one hundred pounds and a dry-pipe system having a similar pressure in the supply-main beyond the main valve and an air-pressure in the distributing-pipes of between fifteen and sixty pounds, so that no matter which system this device is used with the letting in of the water through the main valve will cause the finger to pass onto plate 30 and remain there, thereby causing a continuous ringing of the alarm. When used with a wet-pipe system, the relieving of the high pressure in the sprinkler-pipes by the opening of one or more of the automatic nozzles or by leakage allows the index-finger to simply move back into contact with plate 30; but when used in connection with a dry-pipe system the escape of the air from the sprinkler-pipes brings the index-finger back first on plate 29, and thus rings a preliminary alarm, and while the finger is thus in contact with plate 29 and is approaching zero the main valve is opened by suitable well-known mechanism and the water from the supplymain let in, whereupon the increased pressure from the water causes the finger to move back to plate 30 and remain thereon and ring a continuous alarm until an attendant cuts otf the supply through the main valve. It will be seen also that in case of accidental leakage of air the index-finger will cause an alarm as soon as it touches contact-plate 29, and as it will move slowly across the same by reason of the slow escape of the air an attendant will have time to examine the face of the indicator and lock the main valve closed before it is opened by the automatic mechanism, and thus prevent the unnecessary flooding of the sprinkler-pipes. It will thus be seen that it is essential to employ two separated contact-platcs connected in circuit with each other and the alarm mechanism and the battery-power and to locate one con tact-pl ate nearer zero than the other.

From the foregoing description it is evident that I have provided a combined visual indicator and alarm, each one of which is located in an apartment of a building and which not only sounds the alarm automatically,but also indicates the pressure. It is also further evident that I provide an alarm electrically operated without the use of wires extended to the valve,which in other systems,as described, initiates the operation of the alarm.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is-

1. In combination with a dry-pipe fire-extinguishing system, of an alarm apparatus connected to the dry pipes and consisting of means for causing a preliminary alarm upon the escape of the air and a subsequent or final alarm upon introduction of the water into the dry pipes, for the purpose set forth.

2. In combination with a fire-extinguishing system of the dry-pipe order, of an alarm apparatus connected to the dry pipes thereof and consisting of means for sounding an alarm upon escape of air from the dry pipes and means for sounding a subsequent continuous alarm upon introduction of water into thc dry pipes, for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

FRANK GRAY.

Witnesses:

CHAS. O. BULKLEY, L. M. BULKLEY. 

